neo4j-developer-manual-3.1-java

The Neo4j Developer Manual

v3.1

Table of Contents

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê1

1. Neo4j highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê2

2. Graph database concepts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê3

Get started. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê8

3. Install Neo4j . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê9

4. Get started with Cypher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê10

10. Query Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê176

11. Execution Plans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê190

Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê217

12. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê219

13. Get started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê220

14. Configure and connect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê222

15. Run statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê227

16. Process results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê231

17. Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê235

18. Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê236

23. Authentication and authorization plugins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê260

Appendix A: Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê264

24. Neo4j Status Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê265

Appendix B: Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ê270

© 2017 Neo Technology

License: Creative Commons 3.0

This is the developer manual for Neo4j version 3.1, authored by the Neo4j Team.

The main parts of the manual are:

• Introduction — Introducing graph database concepts and Neo4j.

• Get started — Get started using Neo4j: Cypher and Drivers.

Introduction

This chapter introduces graph database concepts and Neo4j highlights.

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Chapter 1. Neo4j highlights

Connected data is all around us. Neo4j supports rapid development of graph powered systems that

take advantage of the rich connectedness of data.

A native graph database: Neo4j is built from the ground up to be a graph database. The architecture

is designed for optimizing fast management, storage, and traversal of nodes and relationships. In

Neo4j, relationships are first class citizens that represent pre-materialized connections between

entities. An operation known in the relational database world as a join, whose performance degrades

exponentially with the number of relationships, is performed by Neo4j as navigation from one node to

Whiteboard friendly: The property graph approach allows consistent use of the same model

throughout conception, design, implementation, storage, and visualization of any domain or use case.

This allows all business stakeholders to participate throughout the development cycle. With the

schema optional model, the domain model can be evolved continuously as requirements change,

without penalty of expensive schema changes and migrations.

Cypher, the declarative graph query language, is designed to visually represent graph patterns of

nodes and relationships. This highly capable, yet easily readable, query language is centered around

the patterns that express concepts or questions from a specific domain. Cypher can also be extended

for narrow optimizations for specific use cases.

Supports rapid development: Neo4j supports fast development of graph powered systems. Neo4j’s

support business-critical and high-performance applications. It can store hundreds of trillions of

entities for the largest datasets imaginable while being sensitive to compact storage. Neo4j can be

deployed as a scalable, fault-tolerant cluster of machines. Due to its high scalability, Neo4j clusters

require only tens of machines, not hundreds or thousands, saving on cost and operational complexity.

Other features for production applications include hot-backups and extensive monitoring.

Neo4j’s application is only limited by your imagination.

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Chapter 2. Graph database concepts

This chapter contains an introduction to the graph data model.

A graph database stores data in a graph, the most generic of data structures, capable of elegantly

representing any kind of data in a highly accessible way.

A graph records data in nodes and relationships. Both can have properties. This is

sometimes referred to as the "Property Graph Model".

The fundamental units that form a graph are nodes and relationships. In Neo4j, both nodes and

The next step is to have multiple nodes. Let’s add two more nodes and one more property on the

node in the previous example:

Relationships organize the nodes by connecting them. A relationship connects two nodes — a

start node and an end node. Just like nodes, relationships can have properties.

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